Improvement in chucks for metal-lathes



UNITED STATES PATENT OEEIoEc JOHN H. VINTON, OF BRIDGEPORT, CONN., ASSIGNOR OF HIS RIGHT TO GEORGE DOOLITTLE AND FRANK ARMSTRONG, OF SAME PLAGE.

`IMPROVEMENT IN CHUCKS FOR METAL-LATHES.

Specification forming part of Letters Patent No. 154,162, dated August 18, 1874; application filed June 16, 1874.

To all whom t may concern:

Beit known that l, J. H. VINTON, of Bridgeport, in the county of Fairfield and State of Connecticut, have invented certain new andnseful Improvements in Chucks for Lathes; and I do hereby declare thatthe following is a full and exact description thereof, reference being had to the accompanying drawings making a part of this application.

To enable those Skilled to more fully understand the construction and operation of my improved chuck, I will proceed to describe the same, referring by letters to the accompanyingdrawing, in Which- Figure'l is a side elevation, Fig. 2 an end view, Fig. 3 a rear-end view, of the front shell; Fig. 4, a longitudinal section, Fig. 5 a back view, of one of the beveled pinions and friction-plates Figs. 6 and 7, tools used to set up any one or more of the jaws by hand; and Fig. 8 is a perspective view of one of the jaws.

Similar letters of reference indicate like parts in the several iigures.

A is the front shell, and B the rear shell. The front shell A is cut away at a, forming openings for the introduction of the jaws C, which are of the form seen at Fig. 8, the recesses seen at l 1 taking a bearing on corresponding shoulders in the shell A, whereby they are held in place `against any longitudinal thrust, the jaws O G extending rearward flush with the face of the hub D of the shell A, and resting against the face of the main bevel-gear, as will be presently explained. The shellAis stepped at 2 3, (see Fig. 4,) which thus forms the hub D, and at the same time adapts the front shell to perfectly fit within the rear shell B. The object of the hub is to hold the jaws more firmly, and at the same time prevent the ingress of chips or dirt (which would interfere with their proper working) to the driving-gear and pinions. Suitable recesses are formed in the shell A, to permit the introduction of the pinions b and bushing-nuts b', the bushing b having cnt on its circumference a suitable male thread, moving in a corresponding female thread in the shells A and B, as

clearly seen at Fig. 4. The bushing-nuts b" are adapted to receive the shank or spindle of the pinions, which, in turn, are threaded internally, to run upon the thread of the arms c of the jaws O. They are not specially adapted to serve as bearings for the hollow shanks of the pinions, though they incidentally perform that function; but being of the same diameter throughout their whole extent, they are capable of being run in or ont to compensate for wear, or for the purpose of truing7 or centering the jaws. The pinion b is formed with a hollow shank, d, fitting closely but loosely in the bushing b, being suitably nicked to receive the key, (shown at Fig. 6,) whereby the pinion may be turned. c is a washer or friction-plate, formed as clearly seen at Fig. 5. lt has extensions or ears adapted to be located within the recesses e in the shell A, and be covered by the face of the shell B when in its proper relation to shell A, so that the washer c will thus be held against turning; and, being located on the shank of the pinion b, and between the back side of the said pinion and the bushing b', it takes the friction.. from the pinion off from the bushing, and thus prevents the latter, from being, by such friction, run back, which would disarrange the adjustment. The front end of the pinion b is provided with a female thread, adapted to receive the thread of the screw c, secured to the interior back side of the jaw C, whereby the rotation of the pinion b will cause the jaw O to approach or recede from the center. The pinion is held in position between the washer c and a sqnaredw n Y face, f, on the hub D. The rear shell B is cut away correspondingly with shell A, to embrace the bushings b properly, and is also cut away suitably to receive the bevel drivinggear E, the hollow shank or stem F of the gear E extending centrally through to the rear, the bore of this shank being slightly tapering, to receive the tapered end of the lathespindle, whereby a connection with the chuck is effected. The rear end of this stem or shank F is threaded, to receive a ring-nut, G, which may be run up to an intermediate ring or washer, H, and thus hold the main gear in proper position, and when run hard up against the ring, so tightly clamps the gear E to the rear shell that the chuck may be reversed to withdraw the borin g-tool without `affecting the pinions b or loosening the hold ofthe jaws C.

I represents a handle, which, for convenience ot' illustration, I have shown in the drawing, but it is intended to show the connection between the chuck and the spindle of the lathe. The front shell A and rear shell B are secured to each other in their proper relative position by screws or screw-bolts K, passing through suitable holes L in the front shell, the threaded portions of the screws taking into threaded holes in the rear shell B.

It will be seen, by reference to Fig. 4, that when the parts are secured together, the rear ends of the jaws C rest against and are braced by the front face of the bevelgear E longitudinally, and that they are otherwise firmly held within the shell A. It will also be seen that the rear ends of the jaws C and the hub Dare in the same plane, so that vthe whole face of the driving bevel-gear E is. covered by them jointly, and no dirt or chips can reach the cogs or teeth and interfere with their operation. It will be observed that by the bushing b the pinions may (by the use ot' the tool,

`- Fig. 7 be set up to compensate for any wear by friction, or they may be thrown entirely outl of gear with the main driving-gear, whereby any one or more of the jaws may be independently adjusted.v

It will now be readily understood, from the construction and arrangement of the parts, as shown, that, the power or motion being imparted to the lathe-spindle I, thc bevel-gear .E is rotated, which, meshing with the pinions b, rotates them all equally, and they being fixed relatively to the center of the chuck, the screwthreads within them, runnin g on the screws of the jaws, must force the said jaws toward or from the center, so that, by holding the chuck and starting the lathe in the proper direction, the jaws will be run up accurately upon the work, andthe continuous rotation of the chuck will tend to tighten it upon its work, which has, by the same operation, been perfectly centered. The reverse movement of the lathe- -spindle will obviously withdraw the jaws and release the work or tool, except when the nut G is held fast, which would permit the tool or work to be reversed without loosening the jaws.

What I claim as new, and desire to secure by Letters Patent, is-

l. In combination with the jaws C, provided with a stationary screw. c, the revolving nut and pinion b, substantially as and for the purpose set forth.

2.l The combination, with the pinion b and the screw-bushing b', of the washers e, substantially as and for the purpose set forth.

3. In combination with the shell B and driving-gear F E, the ring H and nut G, substantially as and forthe purpose set forth.

4. rIhe hub D on the shell A, adapted to lie against the face of the gear E, in combination with the jaws C, arranged as described, whereby the ingress of chips, &c., is avoided, as set forth.

5. In combination with the shell A B and pinions b, the gear E, constructed as described, and adapted to receive the spindle of a lathe, whereby the gear may become the driver for the chuck after the jaws have ceased movement, substantially asv hereinbefore set forth.

6. In a lathelchuck, the combination of the s shell A B, bushing b', and pinions b, wherebv the jaws of the chuck may be independently adjusted, substantiallyas and for the pur- HENRY E. BowsER, ANDREW E. NAsI-L 

